I am trying to use DynamoDbLocal server for unit test cases.
And came up with two options,
Either define a junit class rule which starts local server before class and stops it after class. So essentially it will start and stop server for each unit test class.
public class MyDynamoDbLocalServerRule extends ExternalResource {
#Override
protected void before() throws Throwable {
myInMemoryDynamoDbServer.start();
}
#Override
protected void after() throws Throwable{
inMemoryDynamoDbServer.stop();
}
OR
Singleton instance :
public static DynamoDBProxyServerContainer createInstance(final int portToListenIn) {
if (dynamoLocal == null) {
synchronized (DynamoDBProxyServerContainer.class) {
if (dynamoLocal == null) {
dynamoLocal = new DynamoDBProxyServerContainer(portToListenIn);
}
}
}
return dynamoLocal;
}
private DynamoDBProxyServerContainer(final int portToListenIn) {
this.startServer(portToListenIn);
getRuntime().addShutdownHook(new Thread(() -> stopServer()));
}
Which one would you recommend and do you have better of doing this ? Please note i should be able to use it with Guice dependency injection framework.
I would recommend Singleton approach as creating the database instance for each test case will be a time consuming option. Also, if you have many test cases, the unit testing is likely to take more time to complete. If you have continuous integration, the build and unit test would take more time.
As the unit tests run in sequential manner, you don't need separate instance for each test case.
Related
I'm writing integration tests using Spring, JUnit 5, JOOQ, TestContainers and Project Reactor. I want to test my repository layer, e.g. verify
Mono<Entity> get(Long id) method.
Therefore, my test should first create entity in database and then verify, that this entity exists. There are two approaches how to do it
Do everything in non-blocking way, e.g.
#Test
public void testGetById() {
var entityPojo = new EntityPojo().setName(UUID.randomUUID());
entityRepository.create(entityPojo)
.zipWhen(e -> entityRepository.get(e.getId()))
.as(StepVerifier::create)
.assertNext(t -> assertThat(t.getT1()).isEqualTo(t.getT2()))
.verifyComplete();
}
Block on create() method
#Test
public void testGetById() {
var entityPojo = new EntityPojo().setName(UUID.randomUUID());
var entity = entityRepository.create(entityPojo).block();
entityRepository.get(e.getId())
.as(StepVerifier::create)
.assertNext(e -> assertThat(e).isEqualTo(entity))
.verifyComplete();
}
Are there any best practices on this? I would prefer second approach, because it's more readable, but may be there are cons of doing it this way, which I'm not aware of?
I am using Redis Server for message broker in my spring boot application.
Is there any simple way to Junit my publish and receive API?
e.g :
Publisher :
public String publish(Object domainObj) {
template.convertAndSend(topic.getTopic(), domainObj.toString());
return "Event Published";
}
Receiver :
public class Receiver implements MessageListener {
#Override
public void onMessage(Message message, byte[] bytes) {
System.out.println("Consumed Message {}" + message);
}
}
I am using JedisConnectionFactory and RedisMessageListenerContainer and RedisTemplate for my implementation
#Configuration
#EnableRedisRepositories
public class RedisConfig {
#Bean
public JedisConnectionFactory connectionFactory() {
RedisStandaloneConfiguration configuration = new RedisStandaloneConfiguration();
configuration.setHostName("localhost");
configuration.setPort(6379);
return new JedisConnectionFactory(configuration);
}
#Bean
public RedisTemplate<String, Object> template() {
RedisTemplate<String, Object> template = new RedisTemplate<>();
template.setConnectionFactory(connectionFactory());
template.setKeySerializer(new StringRedisSerializer());
template.setHashKeySerializer(new StringRedisSerializer());
template.setHashKeySerializer(new JdkSerializationRedisSerializer());
template.setValueSerializer(new JdkSerializationRedisSerializer());
template.setEnableTransactionSupport(true);
template.afterPropertiesSet();
return template;
}
#Bean
public ChannelTopic topic() {
return new ChannelTopic("common-channel");
}
#Bean
public MessageListenerAdapter messageListenerAdapter() {
return new MessageListenerAdapter(new Receiver());
}
#Bean
public RedisMessageListenerContainer redisMessageListenerContainer() {
RedisMessageListenerContainer container = new RedisMessageListenerContainer();
container.setConnectionFactory(connectionFactory());
container.addMessageListener(messageListenerAdapter(), topic());
return container;
}
Unit Testing Receiver and Publisher implementation is quite straight.
JUnit 5 coupled with Mockito extension should do the job.
For example for testing that :
public String publish(Object domainObj) {
template.convertAndSend(topic.getTopic(), domainObj.toString());
return "Event Published";
}
I expect that topic and template be fields of the current class.
These fields could be set by constructor.
So you could write something that check that convertAndSend() is eventually executed with the correct parameters :
#Mock
RedisTemplate<String, Object> templateMock;
#Test
void publish(){
Topic topicFixture = new Topic(...);
Object domainObjFixture = new FooBar(...);
Publisher publisher = new Publisher(templateMock, topicFixture);
//when
publisher.publish(domainObjFixture);
// then
Mockito.verify(templateMock)
.convertAndSend(topicFixture.getTopic(), domainObjFixture);
}
But I don't think that the unit test of these two classes be enough because it never tests the final things : the JMS processing performed by Redis backend.
Particularly, the RedisConfig part that you set with specific things as serializers that have important side effects on the processing.
For my part, I try to always write integration or partial integration tests for Redis backend stuffs to ensure a good no regression harness.
The java embedded-redis library is good for that. It allows to start a redis server
on localhost (works on Windows as well as on Linux).
Starting and stopping the redis server is as simple as :
RedisServer redisServer = new RedisServer(6379);
redisServer.start();
// do some work
redisServer.stop();
Move the start() in the #BeforeEach and the stop() in the #AfterEach and the server is ready.
Then it still requires some adjustments to ensure that the redis configuration specified in Spring is well setup during the tests while using your local redis server and not the "real" redis server. Not always simple to set but great when it is done !
The simplest way to unit test this is to use embedded-redis module. What you do is in BeforeAll you can start embedded Redis and stop the embedded Redis in AfterAll method.
You can also PostConstruct PreDestroy annotations to accomplish this.
If you're looking for Junit5 then you can find the code in my repo here
See BootstrapRedis annotation and their usage here
https://github.com/sonus21/rqueue/blob/7ef545c15985ef91ba719f070f7cc80745525047/rqueue-core/src/test/java/com/github/sonus21/rqueue/core/RedisScriptFactoryTest.java#L40
I am writing unit test for the below code using junit and mockito
public class Abc implements Runnable
{
private static ServerSocket server;
private static int port;
public Abc(int cPort)
{
port = cPort;
}
public void run()
{
init();
}
public static void init()
{
try {
server = new ServerSocket(port);
...something...
client.close();
}
}
catch(IOException e)
{
System.out.println("Exception inside init()...");
e.printStackTrace();
}
}
};
Unit test I have written
#RunWith(PowerMockRunner.class)
#PrepareForTest({ServerSocket.class})
public class abcTest {
#Mock (name = "server") //same name as private var.
ServerSocket mockServer;
#InjectMocks
Abc abc;
#Test
public void testInit() throws Exception {
int port = 1880;
Socket mockClient = Mockito.mock(Socket.class);
PowerMockito.whenNew(ServerSocket.class).
withArguments(anyInt()).thenReturn(mockServer);
abc = new Abc(port);
Abc.init();
PowerMockito.verifyNew(ServerSocket.class).withArguments(port);
}
};
But the call always go to original function definition. I am using junit 4.11 with mockito 2.28.2 and powermockito 2.0.2. I'm using java after a long time. Now its feel like kind of new. Please correct me if anything wrong in the code also.
You will need to change your PrepareForTest annotation
to #PrepareForTest({Abc.class}).
From the PowerMockito docu:
This annotation tells PowerMock to prepare certain classes for testing. Classes needed to be defined using this annotation are typically those that needs to be byte-code manipulated
In this case that refers to the class which creates the new instance of ServerSocket. ServerSocket itself is a non-final public class that does not require special handling from PowerMockito (instead Mockito can deal with this class on its own).
You could also change your test to do the following:
#Test
public void testInit() throws Exception {
int port = 1880;
ServerSocket mockServer = Mockito.mock(ServerSocket.class);
PowerMockito.whenNew(ServerSocket.class)
.withArguments(Mockito.anyInt()).thenReturn(mockServer);
Abc.port = port;
Abc.init();
PowerMockito.verifyNew(ServerSocket.class).withArguments(port);
}
(This first point is unrelated to whether the test fails or succeeds)
I do not know why you mix object's and static method behaviour together, but I think you should change that.In the test instead of creatic an ABC object, just could just set the static port variable directly.
Or alternatively change the whole ABC class into an object.
#InjectMocks failed for me as there is no default constructor
(Actually I got an error message in the console when trying to execute your code)
Additonaly you create a new instance of ABC in your test, which would have overwritten the things done by the annotations. Also as server is created during the init call, there is no need to inject a mock for it.
powermockito 2.0.2 actually depends on junit 4.12, so I am not sure what effects downgrading to an older version might have.
Socket mockClient seemed somewhat unrelated to the code your posted, so I removed it from my example in the answer, however as you use a client (I assume that is your Socket) in your code your probably need to do some mocking for that as well and provide the mock to the method accordingly.
I have a class which has both static and non static methods and would like to write unit test cases for the same.
ClassA{
static getInstance()
{
// to do logic
}
void log()
{
system.out.print();
}
}
And the test case for classA is
ClassTest
{
public void setup()
{
PowerMockito.mockStatic(ClassA.class);
mockA = PowerMockito.mock(ClassA.class);
Mockito.when(ClassA.getInstance("user")).thenReturn(mockA);
Mockito.doNothing().when(mockA).log(Mockito.anyString(), Mockito.anyString(), Mockito.any(Exception.class), Mockito.anyMap());
enter code here
}
}
When i call log method, i am getting exception. How do we mock this?
Serious answer: don't do that.
Simply avoid writing production code that requires PowerMock; for example because you are mixing in calls to static methods.
Typically, a "need for PowerMock" directly translates to: your design needs to be improved!
You will find pretty quickly that PowerMock creates more problems that it is solving. Thus: avoid using it.
Hi I am new to unit testing. Is it possible to access methods that are private?
A very simple example
ObjectA
----------
File file;
private void setupFile (){
//do something
file = "C:\file.dat"
}
In TestCase
File sth = ObjectA.setupFile();
assertNotNull(sth);
I am unable to test whether the file variable is null in method ObjectA.setup()
as I cannot run ObjectA.setupFile()
I am not sure about whether doing like this make sense in terms of unit testing.
So is that a better practice to write every method returning sth and set them public for easier unit testing?
Thanks in advance
In general, you should avoid changing the access of a method/field to enable testing. If you do this then you risk developers using the method directly.
However, if you do need to, then making it protected as Deco says is a good way, so it's accessible from the JUnit tests. If you do this, make sure that it is well documented that this is an method for internal use.
A better way is to test the behaviour of the public methods; you shouldn't care about internal implementation details of a class, so you should only be testing public methods. It's hard to tell from your code, but presumably, the setupFile() has effects later on other methods, so you can test those effects, not the fact that file is not null.
External dependencies (such as dependencies on file system, environment variables) can be worked around in your tests, or injected directly into the class. For the general principle, see my answer to How to test code dependent on environment variables using JUnit?
If it is not absolutely necessary to have the method as private, you can have it as package private (i.e. default access) so that you can call it directly in a JUnit test.
Package private methods can only be used in the package that they are declared, and do not become part of the API of the class. You declare a method package private by putting no modifier on it's declaration.
Here's an example to demonstrate:
public class MyClass() {
int foo;
public MyClass() {
this.foo = 0;
}
void notSoComplexCalculationMethod(int a) {
foo = a * 2;
}
//Other methods here . . .
}
public class MyClassTest extends TestCase {
private MyClass myClass;
protected void setUp() {
super.setUp();
myClass = new MyClass();
}
public void testNotSoComplexCalculationMethod() {
int a = 2;
assertEquals(4, myClass.notSoComplexCalculationMethod(a));
//Unit test passes, yay! Now you've tested a package private method.
}
}